Transcript How many hours do guys play video games a day? Efrain Arriaga

How many hours do guys
play video games a day?
Efrain Arriaga, Victor Salgado, Victor Figueroa, Franco Figueroa
Period 3
2012 - 1213
California Standards
•8.0 Student organized and describe distribution
of data by using of different methods, including
frequency table, histogram, standard line and
bar graphs, stem-and-leaf displays, scatter
plots, and box of whisker plots.
•17.0 Students determine confidence interval for
a simple random sample from a normal
distribution of data and determine the sample
size required for a desired margin of error.
•18.0 Student determine the P-value for a
statistic for a simple random sample from a
normal distribution
Hypothesis

We predict that the average guys play
video games a day is between is between
2-3 hours
Data Collection
We used stratified sampling technique , we asked
100 students.
•We chose 25 students from each grade
•Example: We will collect data by using the stratified
sampling method. We collected data from students
chose by us and divide it into freshman, sophomore,
juniors and seniors.
•
Data
Freshmans:6,4,0,0,1,3,7,2,3,2,3,1,2,2,2,3,5,4,
3,3,0,3,2,3,3
Sophomores:3,1,3,4,2,1,1,3,1,1,1,2,3,1,2,3,4,
5,2,3,1,2,4,3
Juniors:3,2,3,2,4,2,0,0,0,1,2,4,5,3,2,2,2,1,2,3
,4,2,1,3,4,2
Senior:2,3,0,0,2,2,1,0,1,4,1,3,2,4,5,0,0,2,1,3,
4,3,2,2,1
Statistics

•From our survey student’s sample mean
time is 2.29 hours with sample standard
deviation 1.430349608 hours.
Confidence Interval

We are 95% confident the mean hours
guys play video games is between
2.0097~2.5703
Hypothesis Testing
Hypothesis
 •Test Statistics
 •At 5% level of significance, we failed to
reject . There is enough evidence to
support our claim.

Error Analysis
•Our sample mean is 2.29 hours, and the
95% confidence level for the population
mean is between 2.0097~2.5703 hours.
The marginal error is about 5% minutes.
 •Our sample error is due to possible
under-representation of the population.
We might need to take more samples due
to student absences.

Conclusion
We hypothesized that Century students
play 2-3 hours of video games daily.
 survey of 100 male students, we find the
sample mean 2.29
 We were slightly correct.
